$x+15\%.x=\dfrac{(1,09-0,29).\dfrac{5}{4}}{(18,9+16\dfrac{13}{20}).\dfrac{8}{9}}$
$\to x+0,15x=\dfrac{\dfrac{4}{5}.\dfrac{5}{4}}{(\dfrac{189}{10}+\dfrac{333}{20}).\dfrac{8}{9}}$
$\to 1,15x=\dfrac{1}{\dfrac{711}{20}.\dfrac{8}{9}}$
$\to \dfrac{23}{20}x=1:\dfrac{158}{5}$
$\to \dfrac{23}{20}x=1.\dfrac{5}{158}$
$\to \dfrac{23}{20}x=\dfrac{5}{158}$
$\to x=\dfrac{5}{158}:\dfrac{23}{20}$
$\to x=\dfrac{50}{1817}$
Vậy $x=\dfrac{50}{1817}$